Coil planet centrifuge devices for particle separation were first developed employing end-closed coiled tubes. This type of centrifuge device is described in U.S. Pat. No. 3,420,436 to Y. Ito. This original type of centrifuge apparatus was designed to obtain predetermined specific rotation/revolution (r/R) ratios of the column holder, such as 1/100, 1/200, 1/300 and 1/500. The capability of the system has been demonstrated by the separation of particles using both single phase and two-phase solvent systems.
However, the above-mentioned prior system lacks continuous flow-through capability, resulting in limited efficiency and in difficulty in the continuous monitoring and fractionization of the separated samples.
Recently, various types of flow-through centrifuge devices have been developed to carry out countercurrent chromatography (U.S. Pat. Nos. 3,775,309; 3,856,669; 3,994,805; and 4,058,460) and cell separations (U.S. Ser. No. 661,114) without the use of rotating seals. However, all these systems have fixed r/R values, of either 1 or zero, and thus lack versatility in separation (also see U.S. Pat. No. 3,986,442).